Technological advances have made it so that many American families and individuals can afford a digital movie camera. These cameras are being used more and more to capture images and then transfer these images via the Internet. Another use of the cameras is for surveillance purposes.
Digital cameras, with motor actuated zoom and focus capabilities, are rapidly becoming the camera of choice for a wide variety of surveillance applications. Many of these cameras come equipped with an automatic iris feature. The automatic iris function allows a selected amount of light to reach the image capturing element of the camera in a wide variety of light conditions. With this feature, image resolution is largely preserved though ambient light conditions may go from bright to dim and vice-versa.
Certain controllers are available for remotely operated video cameras. These controllers are invariably specific to the make and model of the camera and usually offer little capability to adapt to other camera designs. Regarding automatic iris functions, the controllers permit a remote operator to choose to activate or deactivate the function.
With technology ever-improving in the digital camera field, it becomes prudent and at times necessary to replace cameras being used for their more modern successors. In such cases, the remote controllers used with the cameras often will need to be changed and invariably those suited for the new cameras are unique to the camera purchased. The cost of supplying a new controller with each change could rapidly become prohibitive.
It is therefor desirable to have a digital camera controller that is adaptable to a wide-variety of digital cameras, foregoing the need to replace the controller with the acquisition of every new camera. Another desirable feature of such a controller is to provide a remote automatic iris control that is not limited solely to actuating or de-actuating the feature, but that allows a remote viewer to set the automatic iris feature to remain functional at a user-specified light level.
This latter feature will allow a user to accommodate scenes in which a bright object appears in a dark background, or a dark object appears in a bright background. Previous automatic iris functions did not readily accommodate these extremes. In surveillance applications, such tuning of the automatic iris can be crucial, as it can be envisioned that it headlights, flares or other focused light may temporarily blind the view of a remote observer who cannot adjust the iris.
There is thus a need for a digital camera controller that may be used with a wide variety of cameras and that permits the automatic iris function of those cameras to be fine tuned by a user of the camera controller.
The invention provides a camera controller incorporating a microcontroller for carrying out all controller functions. The microcontroller is operably coupled to a reprogrammable memory in which operating commands for the specific camera being used are stored. Thus the controller of the invention can be configured to work with a great number of different cameras and command sets, based upon the specific camera to be controlled. An example memory that can be used for this purpose is an electrically erasable read only memory that, by using a programmable logic array and random access memory, can be reprogrammed in-place. The microcontroller is operably connected to a camera""s xe2x80x9con/offxe2x80x9d, zoom and focus functions so that these may be controlled via the controller. Also controlled by the invention is the automatic iris feature of a digital camera. An exemplary embodiment of the invention uses a multiplying digital-to-analog converter to control analog-formatted iris control devices. The controller is also designed to be used with cameras that utilize digital-formatted iris control devices. In either case, the controller of the invention permits its user to set the automatic iris to a user-specified light income level. The automatic iris will then strive to maintain the same degree of light exposure to its image collector according to this user-set adjustment. Additionally, the user may elect to activate or deactivate the iris control.
It is an object of this invention to improve remote camera control capability.
Another object of this invention is to provide a remote camera controller that can be used with a wide variety of cameras.
Yet another object of this invention is to provide a remote camera controller that controls motor-driven zoom and focus functions of the camera.
A further object of this invention is to provide a remote camera controller that permits control and tuning of an automatic iris feature of a camera so that the iris feature can be actuated or de-actuated and can also be set to remain functional to provide a user specified light income level to the image sensor of the camera.
Still a further object of this invention is to provide all of the above objects to digital cameras.